Some machines produce non-woven continuous mat-like ribbons direct from a carding machine in widths from 500-3000 mm.
Our Australian Patent No. 2006200908 referred to above describes such a machine. This builds a pleated web about 3000 mm wide which is fed into an oven where the fibres introduced during the lapping process become adhesive and bond to the surrounding fibres.
The oven treatment creates a springy, stable ribbon product capable of being wound into rolls or cut into sheets of 50-2500 gsm.
The horizontal comb which pleats the advancing web is fixed to the ends of a row of rods which rise and fall in response to individual reciprocators, each belt driven from a common drive motor. The rod spacing is about 500 mm.
The depth of the pleats is changed by adjusting the height of the lapping zone in which the pleated web advances on its travel through the zone to the oven.
Raising the roof of the zone allows the pleats to be either shallow or deep. The conveyor on which the fibrous web is pushed by the comb advances toward the oven at constant speed. A screw control raises and lowers the roof of the zone so the change from one product specification to another is convenient and rapid.
Increasing the throughput speed presents difficulties in that greater forces act on the comb whereas the drive to the presser bar which inserts needles and filaments into the web must remain synchronised in order to preserve the build of the mat-like product.